The Bills are searching for Chan Gailey’s replacement. They fired him Monday after a second straight 6-10 campaign, which extended their playoff drought to 13 seasons. Every other NFL team has gone to the postseason since the Bills went last.

A source close to the Bills told The News that Brandon is particularly fond of Whisenhunt, who went 45-51 in six seasons with the Cardinals. Whisenhunt oversaw two of the Cardinals’ three winning seasons over the past 28 years and their only Super Bowl trip.

Whaley worked with Whisenhunt, Horton and Grimm when they were in the Pittsburgh Steelers organization together.

“We go way back,” Whaley said Tuesday. “We’ve won some Super Bowls together. So I have high regard for their coaching acumen. Personally, I know those guys. Hopefully, we’ll see what happens.

“We haven’t decided. We’ve still got to figure out what we’re going to do.”

Whisenhunt and Grimm helped Arizona reach the Super Bowl four years ago after winning the NFC West at 9-7. Pittsburgh, with Horton on staff, beat Arizona for the championship.

The Bills also reportedly asked the Denver Broncos for permission to interview offensive coordinator Mike McCoy. NFL rules allow assistant coaches of playoff teams to interview during a bye week, which the Broncos earned by going 13-3.

Other reports have linked the Bills to Syracuse head coach Doug Marrone and former Oakland Raiders head coach and current Cincinnati Bengals assistant Hue Jackson.

Another league source told The News former Chicago Bears coach Lovie Smith wants to interview with the Bills. Smith took Chicago to the Super Bowl six years ago. He went 81-63 in nine years there.

This search already feels much different than the last one. The Bills fired Dick Jauron with seven games left in the 2009 season.

The Bills had trouble selling themselves to prospective candidates. They courted the likes of Mike Shanahan, Bill Cowher and Jon Gruden with no success.

The Bills approached Grimm, but serious talks never materialized. New York Jets offensive coordinator Brian Schottenheimer declined the chance to interview.